LTC3610
24V, 12A Monolithic
Synchronous Step-Down
DC/DC Converter
DESCRIPTION
FEATURES
TheLTC®3610isahighefficiency,monolithicsynchronous
step-down DC/DC converter that can deliver up to 12A
output current from a 4V to 24V (28V maximum) input
supply. It uses a valley current control architecture to de-
liver very low duty cycle operation at high frequency with
excellent transient response. The operating frequency is
selected by an external resistor and is compensated for
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12A Output Current
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Wide V Range = 4V to 24V
IN
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Internal N-Channel MOSFETs
True Current Mode Control
Optimized for High Step-Down Ratios
t
≤100ns
ON(MIN)
Extremely Fast Transient Response
Stable with Ceramic C
variations in V and V .
OUT
IN
OUT
1ꢀ 0ꢁ.V Voltage Reference
Power Good Output Voltage Monitor
Adjustable On-Time/Switching Frequency
Adjustable Current Limit
The LTC3610 can be configured for discontinuous or
forced continuous operation at light load. Forced continu-
ous operation reduces noise and RF interference while
discontinuous mode provides high efficiency by reducing
switching losses at light loads.
Programmable Soft-Start
Output Overvoltage Protection
Optional Short-Circuit Shutdown Timer
Low Shutdown I : 15μA
Available in a 9mm × 9mm 64-Pin QFN Package
Fault protection is provided by internal foldback current
limiting,anoutputovervoltagecomparatorandanoptional
short-circuitshutdowntimer. Soft-startcapabilityforsup-
ply sequencing is accomplished using an external timing
capacitor.Theregulatorcurrentlimitisuserprogrammable.
A power good output voltage monitor indicates when
the output is in regulation. The LTC3610 is available in a
compact 9mm × 9mm QFN package.
Q
APPLICATIONS
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Point of Load Regulation
Distributed Power Systems
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L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners. Protected by U.S. Patents including
5481178, 6100678, 6580258, 5847554, 6304066.
TYPICAL APPLICATION
High Efficiency Step-Down Converter
Efficiency vs Load Current
100
95
90
85
80
75
70
65
60
55
50
10000
1000
100
10
604k
V
I
0.1μF
ON
ON
V
= 5V
IN
V
IN
4V TO 24V
RUN/SS
V
IN
10μF
×3
V
= 12V
IN
100pF
LTC3610
0.47μH
0.22μF
V
2.5V
12A
OUT
SW
470pF
31.83k
100μF
×2
I
TH
BOOST
POWER LOSS 12V
POWER LOSS 5V
0.1
SGND INTV
CC
30.1k
9.5k
FCB
V
OUT
= 2.5V
10
1
4.7μF
V
RNG
0.01
1
PGND
PGOOD
LOAD CURRENT (A)
3610 TA01b
EXTV
CC
V
FB
3610 TA01a
3610fd
1